Permanent mold



Nov. 20, 1934. H. w. BIRINGER} 1,981,580

PERMANENT MOLD Original Filed May 31, 1932 2 Sheets-Sheet l s 3 21 /O 55 a, //9 Q\[/\32 Z28 B 28a 52 29 37 25 /7 Z 4 55 56 Z/ l 6 5 6 7 I /Z F1 E a I /4 W INVEZZTOKR W I BY i ATTORNEYS NOV. 20, 1934. H, w B]R|NGER 1,981,580

PERMANENT MOLD Original Filed May 31, 1932 2 Sheets-Sheet 2 7 INVENTOR F1 0 E0 WEI/"1M W iv, r M:

ATTOR N EY6 1 Patented Nov. 20, 1934 UNITED STATES PERMANENT MOLD Herman W. Biringer, Cleveland, Ohio, assignor to The Pcrmold Company, Cleveland, Ohio, a

corporation of Ohio Application May 31, 1932, Serial No. 614,521 Renewed September 20, 1934 Claims.

This invention relates to molds for casting metal, and particularly to permanent molds.

The formation of relatively thin-walled castings, such as washing machine agitators and simi- 5 lar articles, from metal having an aluminum base and of comparatively low melting point, presents exceedingly difiicult casting problems. In order that such thin-walled castings may be free from voids and cold shuts and streaks of porosity, it is desirable to introduce the metal uniformly at substantially the same temperature throughout the entire casting cavity. It is also desirable to operate the mold at a uniform quick rate which requires as a rule special means of clamping in order to avoid unnecessary delay. In the mold construction to which the present invention is applied, the molten metal is conducted-to a ring sprue cavity adjacent the base of the casting from a plurality of pouring sprue cavities, and is in- 20 troduced into the base of the casting cavity at a plurality of points through gates, and in order to permit easy removal of the casting the mold comprises a plurality of sections, several of which are removable.

It is essential that the cooperating mold sections which are recessed to provide the casting cavity be brought into their proper relationship and maintained in such relationship during the entire casting operation of the article.

It is one of the objects, therefore, of the present invention, to provide a permanent mold having a plurality of mold sections with an improved clamping means which is adapted to cooperate freely and easily with the mold sections so as to force them into cooperative relationship, and to hold them in such relation while the articles are being cast.

Another object is to provide a permanent mold having a stationary mold section and movable mold sections, with a new and improved clamping means for securely holding the movable sections against the stationary section during the casting operation.

Another object is to provide a permanent mold having a stationary mold section and movable mold sections, with a means for properly centering the movable sections with respect to each other and with respect to the stationary mold sec & tion, and to clamp the same together during the casting operation.

A further object is to provide a permanent mold having a stationary mold section and a plurality of movable mold sections with a clamping means which may be quickly and easily operated to locate the movable sections on the stationary section, and to clamp the same thereto.

With the above and other objects in view which will be apparent from the following detailed description, the present invention consists in certain features of construction and combinations of parts which will be readily understood by those skilled in the art to which the invention appertains.

In the accompanying drawings which illustrate suitable embodiments of the present invention,

Figure 1 is a plan view of one type of permanent mold in which the improved clamping means is incorporated; a l n Fig. 2 is a section taken approximately on the 7 line 22 of Fig. 1, showing the detail construction ,of the permanent mold and clamping means, one

of the mold sections being shown in dotted outline in its open position; v i

Fig. 3 is an enlarged section taken approximately on the line 33 of Fig. 1, showing the clamp in detail;

Fig. 4 is a plan view of the clamping device in its casting position, the mold sections being shown in dotted graphical outlines;

Fig. 5 is a plan view of a modified clamp which may be used for permanent molds having four movable mold sections; and

Fig. 6 is a section taken approximately on the line 66 of Fig. 5.

For the purposes of illustration, there is shown in the drawings a permanent mold suitable for casting such thin-walled articles as a washing machine agitator. As shown in Fig. 2, the agitator comprises a central hollow stem A extending up- Wardly from a bell-shaped base B and having three radially extending wings C formed on its outer surface which extend from the bell-shaped base B substantially to the upper end of the stem portion A.

Referring to the accompanying drawings in which like numerals refer to like parts throughout the several views, the mold construction in which the present invention is incorporated comprises a suitable base 1 upon which a stationary mold section2 is mounted, and to whichv the movable mold sections 3 are hinged for swinging movement. As shown in Figs. 1 and 2, three movable mold sections are employed, although four or more, or even two movable mold sections may be utilized.

In the construction shown in Fig. 2, the base 1 is provided with a supporting top a having a central opening 5 therein which is defined by a continuous circular flange 6 depending from the supporting top 4. This top 4 is formed with a circular recess extending to the central opening 5 and receives the annular stationary mold section 2, the stationary section 2 having a depend ing circular flange 7 which fits snugly within the central opening 5 of the supporting portion 6 to properly locate the lower section 2 on the base.

As shown in the drawings, the movable mold sections 3 seat in their operating position on the mold sections 2, and each of these sections comprises an arcuate bottom portion 8, 120 in extent, which seats on the stationary section 2, a central upwardly extending portion 9, and vertical wing portions 10, 120 apart,'extending upwardly from the bottom portion 3 and being, integral with the bottom and central portions.

The bottom portions 8 and central portions 9 of the movable sections are internally recessed in such a manner when they abut each other as to provide the casting cavity for the article to be cast and, as illustrated in Fig. 2, the recesses in the central portions 9 form the casting cavity for the stem A and the recesses in the bottom portion 8form the casting cavity for the bell B of the agitator. The casting cavities for the agitator wings C are formed in the wings 10, of the movable sections. A portion of the configuration of the bell of the agitator is also formed in the annular stationary mold section 2, and since in the case here shown the agitator is hollow, a movable core 11 is provided to extend into the casting cavity provided by the, three movable mold sections but spaced from the walls thereof to give the proper thickness of metal, the surfaces of the core and a portion of the surface of the stationary section forming the inner face of the agitator when the metal is introduced into the casting cavity. The core 11 .is provided with a base-12 which'is arrangedto reciprocate within the flange '7 of the stationary section and-in order to provide this reciprocation to withdraw the core, the base 12 is provided with arack .13 which may be actuated by a pinion '14.

The molten metal is introduced intoa cavity 15 provided by mating recesses formed in the central upwardly extending portions of the movable mold sections 3, which cavity 15 communicates with distributing sprue cavities 16 which lead to a substantially continuous ring sprue cavity 1'7 disposed radially outside of the bell portion B of the agitator. The distributing sprue cavities 16 are formed by channel-shaped grooves provided in the abutting wings 10 of the movable mold sections and the'peripheral ring sprue cavity is preferably provided by forming a portion of the same in the stationary mold section and the remainder thereof in the movable mold sections. The metal is introduced into the'mold' cavity from the ring sprue cavity 17 through suitable gates 18 provided about the periphery of the casting cavity so that the molten metal may be introduced into the casting cavity-at a plurality of points about the periphery thereof. i

As shown in Figs. 1 and 2, each of the movable mold sections is provided with outwardly extending pivot arms 19 disposed a slight distance above the'bottom portion 8 thereof and which are hinged at their outer ends by means of a hinge pin 20 to an extending arm 21 of thebase l. The arms 19, however, have a loose connection with the pivot pin 20 in order to provide a slight movement of the mold section relative to the pins 20 to permit the same to be properly located by the action of the clamp, to be described, on

"1 the stationary mold section.

It is obvious from theforegoing description of the mold that the article to be cast has a relatively thin wall and that in the casting operation the molten metal is introduced into the bottom of the casting cavity which, in view of the fact that a number of movable mold sections are employed, makes it necessary that the movable mold sections be properly located with respect to each other and with respect to the stationary mold section, and also that the sections be very securely clamped together. This clamping and centering operation should be carried out in a reasonable and uniform time cycle.

The clamping means of the present invention in its one form comprises an endless element 22 normally seating on the supporting top 4 of the base 1 and surrounding the annular stationary mold section 2 and the movable mold sections 3.

The metal at the outer periphery of the stationary mold section is chamfered to provide a beveled surface 23 extending longitudinally outwardly and upwardly from the lower portion to the parting line between the stationary mold section and the movable mold sections, and the movable mold sections are correspondingly formed with bevel surfaces 24 which converge toward the beveled surface 23 of the stationary mold section 2.

The endless element 22 is provided with a pair of'fixed clamp portions 25 arranged 120 apart and-have arcuate V-shaped grooves therein, the walls of which grooves are arranged at the same angle asthe beveled surfaces 23 and 24 of the mold sections. The endless element also has a movable clamp element 2'7 disposed coincident with the line which intersects the angle between the clamp elements 25, and the movable element 27 is also formed with an arcuate V-shaped groove 28. The element 2'7 is mounted for sliding movementin the element 22, it being guided within a opposite sides by means of links 32 to the movable clamp element 2'7, the links 32 being pivoted by means of pins 33 to the element 2'7 and by means of pins 34 to the nut 29, the links 32 having elongated slots 32 for the receptionof the pins 34 to provide a lost motion movement.

The nut 29 also carries a threaded shaft 35, the end of which is arranged to be threaded against the seat in a recess 36 formed in the end of the movable clamp element 27. The screw shaft 85 is provided with transversely extending arms 3'7 which can be grasped to rotate the same.

In order to provide for successful operation of the clamping device described, the horizontal face of the supporting portion 4 uponwhich, the cir cular element 22 seats should be accurately machined so that the apices of the V-grooves of the clamping portions and thernachined face or parting lin-e face of the stationary mold section 2 will lie in the same plane. Furthermore, the radii of the upper inner axial faces of the clamping portions 25 and 27, when these portions are in closed clamping position, are such that they movable sections on their pivot pins 20 and in this position'the element 22 of the clamping device assumes the position shown in dotted outline in Fig. 2, the portions 25 thereof being radially outwardly of the beveled surface 23 of the stationary section and the movable element 27 being retracted out of engagement with the beveled surface 23. When it is desired to operate the mold, the movable sections are swung over 'onto the stationary section 2 in their approximate relative positions, and the nut 29 is then pivoted about the pins 30 to a horizontal position, as indicated in Fig. 2, which causes the sliding element 27 to engage with the beveled surface 24 of the adjacent movable section 3 and which, through the toggle action, moves the endless element 22 relative to the mold sections and toward the element 27 to bring the upper walls of the V-shaped grooves of the clamp portions 25 into engagement with the beveled surfaces 24 of the other two' mold sections. The screw shaft is then rotated by grasping the handle 37, which causes the sliding element 2'? and endless element 22 to move relative to each other, and during this movement the upper walls of the V-shaped grooves of the clamping elements 25 and 2'7 outwardly force the movable mold sections into a closer abutting relationship, and also by reason of the fact that as the movable mold sections approximate their assembled closed position, the lower walls of the V-shaped grooves engage with the bevel surface 23 of the stationary mold section to clamp the movable sections firmly against the stationary mold section.

The slot in the ends of the links 32 permits unrestricted turning of the screw shaft 35. This action actually provides a slight movement of the movable mold sections on the stationary section, due to the loose fit of the same on the pivot pins20,to properly locate the same relative to each other and relative to the stationary section so that the portions of the cavities formed in the movable sections and in the stationary mold section will be brought into the proper mating relationship, and also to provide a continuous unbroken casting cavity at the inner surfaces of the movable mold sections which otherwise might be interrupted by the metal at the three parting lines between the movable mold sections.

Although the means for operating the clamping device is shown to comprise a toggle and screw arrangement, it is obvious that the operation of this device may be obtained by a screw arrangement alone or a toggle arrangement alone, or by any other suitable means.

In Figs. 5 and 6 there is shown a clamping device for use in permanent molds having four movable sections. In this arrangement the endless element 40 is supported on the top supporting portion of the mold base in the same manner as shown in Fig. 2, and this element 40 carries two clamping portions 41 at its inner side approximately apart, each of which is formed with a V-shaped arcuate groove 42 in the same manner as the clamping device previously described. The endless element 40 also carries directly opposite the clamping portions 41, movable clamping portions 43 which slide in the element and are actuated by a suitable screw 44, each of the slidable portions being provided with an arcuate V- shaped groove 45.

The walls of the V-shaped grooves in the clamping portions 41 and 43 correspond with the bevel surfaces 23 and 24 of the mold sections and in their operation function in the same manner as the clamping device previously described, each of the rigid clamping portions engaging with a movable mold section and each of the movable clamping portions engaging with a movable mold section to thereby, when the screws 44 are tightened, locate the movable mold sections relative to each other on the stationary mold section and to securely clamp these movable mold sections to the stationary mold section.

Although the clamping surfaces of the clamp device and mold sections are shown to be angleshaped, it is to be understood that they may be of any suitable contour.

Furthermore, it is to be understood that the particular forms of apparatus shown and described, and the particular procedure set forth, are presented for purposes of explanation and illustration and that various modifications of said apparatus and procedure can be made without departing from my invention as definedin the appended claims. 7

What I claim is: 1. In a mold having a stationary mold section and plurality of mating movable mold sections seating against said stationary mold section when the mold is closed, said movable and stationary sections having peripheral edge portions converging toward each other, an element surrounding the peripheral edge portions of said stationary section, clamping portions carried by said element each having a V-groove therein substantially corresponding to said converging edges of said mold sections for engagement therewith, one or more of said clamping portions being movable relative to said element, and screw means carried by said element for moving said movable clamping portion relative thereto whereby the walls of said V-grooves engage with the converging edges of said mold sections and cause said movable mold sections to be clamped to said stationary mold section during relative movement of said movable clamping portion and carrying element. i

2. In a mold having a stationary mold section and a plurality of mating movable mold sections seating against said stationary mold section when the mold is closed, said movable and stationary sections having peripheral edge portions converging toward each other, an element surrounding the peripheral edge portions of said stationary section, clamping portions carried by said element each having a V-groove therein substantially corresponding to said converging edges of said mold sections for engagement therewith, one or more of said clamping portions being movable relative to said element, a pivoted portion carried by said element, and links connecting said pivoted portion to said movable clamping portion, whereby to provide relative movement between said movable clamping por- 1 tion and said element.

3. In a mold having a stationary mold section and a plurality of mating movable mold sections seating against said stationary moldsectionswhen the mold is closed, said movable and stationary sections having peripheral edge portions converging toward each other, an element surrounding the peripheral edge portions of said stationary section, clamping portions carried by said element each having a V-groove therein substantially corresponding to said converging edges of said mold sections for engagement therewith, one or more of said clamping portions being movable relative to said element, a toggle device carried by said element to provide relative movement between said movable clamping portion and element, and screw means also carried by said element to provide further relative movement of said movable clamping portion and element, whereby the walls of said V-grooves engage with the converging edges of said mold sections to thereby clamp said movable mold sections against said stationary mold section.

4. In a mold having a stationary mold section and a plurality of mating movable mold sections seating against said stationary moldsection, when the mold is closed, said movable and stationary sections having peripheral edge portions converging toward each other, an element surrounding the peripheral edge portions of said stationary section, clamping portions carried by said element each having a V-groove therein substantially correspondingto said converging edges of said mold sections for engagement therewith, one or more of said clamping portions beingmovable relative to said element, a nut pivoted to said element, lost motion toggle links connecting said nut 'with said movable clamping portion to provide relative mo tionbetween said movable clamping portion and element, and a 'screw' threaded in said nut to engage said movable clamping portion and proivide further relative movement of said movable clamping portion and element, whereby the walls of said V-grooves engage with the converging edges of said mold sections to thereby clamp said movable mold sections against said stationary mold section.;

5. Ina mold having a stationary mold section and a plurality of mating mold sections seating against each other and against said stationary section when the mold is closed, said stationary section having peripheral edge portions and each of said movable sections having an edge portion adjacent an edge portion of said stationary section, a movable element separate from said sections having clamping portions which engage the peripheral edge of the stationary section and the adjacent edge portions of said movable sections, at least one of said clamping portions being movable relative to said element, and means carried by said element for'providing relative movement between said clamping portion and element to bring said clamping portions into clamping engagement with said edge portions of such sections. v

HERMAN W. BIRINGER. 

